Impact reducing means for mucking machines



Jan. 22, 1952 A. R. BIEDESS IMPACT REDUCING MEANS FOR MUCKING MACHINES 2 SHEETS-SHEET 1 Filed Nov. 16, 1949 Fig.1

Fig. 2

INVENTOR. any Afiimexs flrry Jan. 22, 1952 A. R. BIEDESS IMPACT REDUCING MEANS FOR MUCKING MACHINES 2 SHEETSSHEET 2 Filed Nov. 16, 1949 1? 4 i Ill L a m ATTY.

Patented Jan. 22, 1952 IMPACT REDUCING MEANS FOR MUCKING MACHINES Anthony B. Biedess, Chicago, IlI., assignor to Goodman Manufacturing Company, Chicago, 111., a corporation of Illinois Application November 16, 1949, Serial No. 127,681

4 Claims. 1

This invention relates to improvements in mucking machines and more particularly relates to impact reducing means for mucking machines of the general type illustrated in Patent No. 1,514,008, which issued to J. P. Mosier on November 4, 1924. Mucking machines of the aforementioned type are normally subjected to very rough usage. As rapidly as the heavy scoop-carrying boom can be lifted to discharge, it is dropped to shoveling position for another load. The large heavy duty machines are generally provided with a support or turntable against which the boom strikes, to limit its drop movement. These repeated heavy impacts cause rapid wear on the pins about which the boom swings and cause frequent breakage of parts. Attempts have been made to absorb some of this impact energy by interposing simple spring assemblies between the boom and support. These attempts, however, have been only moderately successful and only on relatively small machines where the amount of energy absorption required at each impact is not high.

An important object of the present invention, therefore; is to provide an improved impact reducing means which will absorb large amounts of energy at the time of impact of the boom on the support.

Other objects and advantages will be apparent from the following description taken in connection with the appended drawings in which:

' Figure 1 is a side view showing in outline a mucking machine utilizing one form of the improved impact reducing means;

Figure 2 is an enlarged fragmentary view of the front portion of the machine shown in Figure 1;

Figure 3 is an enlarged end view of the impact reducing means as shown in the previous figures;

Figure 4 is a sectional view of Figure 3, taken along line 4-4; and

Figure 5 is a sectional view of Figure 3, taken along line 5-5.

Referring now more specifically to the embodiment shown in the drawings, the mucking machine includes a truck or main frame 2| mounted on track Wheels 22, 22. The main frame forms a support for a scoop 23 which is in advance thereof on the end of boom 24.

Various details of the machine which are standard, such as the conveyor 26 and its motor drive (not shown), will not be described in detail because they are well known and understood by those skilled in this art.

The boom 24, which in this case is formed with a troughed section, to act as a chute, to transfer dumped material from the scoop to the conveyor, is pivoted for horizontal swinging movement about vertical king pin 21 and for vertical swinging movement about horizontal pin 28.

The scoop 23 is elevated to a discharge position or swung from side to side by a pair of flexible cables or chains 29, 29, connected to opposite corners thereof, which are its upper corners when the scoop is in the gathering position, as shown in Figure l. The chains are adapted to be wound on or payed off of a pair of winding drums 3i which may be driven and controlled by suitable conventional'means.

The horizontal portion 32 of the truck frame 2i, which extends forwardly beyond the conveyor a substantial distance, forms a support for an intermediate portion of the boom near its rear end when the boom is in its lower or scooping position, and acts as a stop in limiting downward pivotal movement of the boom.

Referring now in particular to the novel impact reducing means, best shown in Figures 3, 4 and 5, a striker bar 33, in this case an inverted railroad type rail, is mounted transversely across the underside of the boom 24 resting on the upper bearing surface 34 of support 32 when the boom is in its lowered position. Each end of the striker bar is connected to the boom by identical arrangements now to be described. The description will be given for the right-hand end of the striker bar, but it will be understood that the left-hand end will be the same.

Atop the end and connected as by rivets 36 is a member 31 having spaced upstanding ears 38' through which is mounted a pivot pin 39. providing lateral flexibility in the assembly, as will be seen. A member 41 having a lower extension 42 pivotally mounted on pin 39 between ears 38, acts as a lower supporting bearing for spring means, in this case the two coil springs 43. Along the upper side wall of the boom a fixed supporting member or plate 44 is mounted as by welding. A plurality, in this case eight, of adjusting screws 46 are threadedly engaged therewith and extend therethrough to comprise means for adjusting the up and down position of a movable adjustment member or plate 41, which forms an upper bearing for the upper ends of springs 43. The latter are thus compressibly interposed between the lower supporting member or bearing 4| and the movable adjustment member or bearing 41, to bias the striker bar downward, away from the boom, towards a relative position indicated in broken lines in Figure 3. This downward bias is adjustable to a desired amount by varying the compression in the springs by turning screws 46 to move the adjustment member 41 up or down. The desired degree of bias when once set may be locked by jam nuts 48.

Hydraulic shock absorbing means, in this case the two hydraulic shock absorbers 49, are con-, nected between the upper and lower supporting member plates 41 and M by means of rubber washers and steel washers and nuts 52 and 53, respectively. The internal construction of the shock absorbers is not shown in detail as many types of commercially available hydraulic shock absorbers, sized to carry. the, particular load involved, may be utilized. It will be pref-- erable in most cases that the shock absorbing means be chosen witlra greater resistance to compression than extension, in order to permit the striker bar to recover quickly to its maximum impact-reducing position (shown in brokenrlines in Figure 3) when the boom is lifted. Means for limiting downward movement of the striker bar relative to the boom comprise in this instance a pair of steps 54 bolted to side plates 55 and engageable with the underside of supporting plate 4! when the impact-reducing assembly is in its above-mentioned maximum extended position.

When the boom is dropped at atime while it is also rotating, there will be a substantial sidewise force. component applied to the striker bar. To preventt'his component being transmitted to the spring and shock absorber assemblies, two vertically extending lugs 51 are carried at each end of the striker bar, each mounted close to the outside surface 58 of a vertical lug 59 welded to the outside of the boom. Each lug 51 is, in this case, part of a built-up assembly generally indicated by -61 (best shown in Figure 5) comprise ing a short plate 62 bolted to the middle section of the rail 33 having spaced ears 63, with a section 54 welded across the ears, lug 51 being welded to the section 64. Thus, the lug assembly 6| limits relative sidewise movement of the striker bar and boom by engagement of the barcarried lug 5'! with the outside surfaces 58 of the boom-carried lugs 59; and limits relative movement along the longitudinal axis of the boom by engagement of the bar-carried surfaces 66 with the boom-carried surfaces 61.

It will be seen that by reason of the pivotal connection, above described, between themember 31 and the lower supporting member 4|, limited relative, sidewise movement between the striker bar and boom (as permitted by the. clearance between lugs 51 and 59) is readily accommodated in the springs and shock absorbers; by a minimum of distortion. Distortion of the shock absorbers themselves under such conditions is further prevented by the flexibility of the rubber bushings 5|.

In operation, when the boom is pivoted upward, the bar 33' will be moved downward, relative to the boom, in an amount indicated by broken lines in Figure 1, this relative position being determined by abutment of the lower spring supporting members 4| with the stops 54.

When the boom is dropped, the impact of the bar 33 striking the support 32 will be reduced by compression of the springs; and shock absorbers, thusgreatly increasing the service life of the main pivot pins 2! and28, aswell as other parts. If the boom is pivotin about the vertical kin 4 pin 21 at the time it drops on the extension 32, the side thrust on the striker bar will be transmitted directly to the boom, and not through the spring and shock absorber assembly, in the manner above described.

While one embodimentpf .the present invention hasbeen shown and described, it willbe apparent that many modifications may be made within the scope of the appended claims.

I claim as my invention:

1. Ina mucking machine, a track mounted main frame, a boom pivotally mounted on said main frame, ascoopmounted on the free end of said boom, means for elevating and swinging said boom from sideto side, a support projecting forwardly from said main frame and adapted to limit downward movement of said boom and formasupport therefor during the gathering operation, a striker bar movable relative to said boomand disposed transversely across the..underside of said boomfor engagement with said support when the boom is dropped, impact reducing means including spring means and hydraulic shock absorbing means interposed between each end of said bar and said boom for reducing the impact loadexerted by the baron the support When the boom is dropped.

2. In a mucking machine, a track mounted main frame a boom pivotally mounted on said main frame, a scoop mounted onthe free end of said boom, meansfor elevating and swinging said boom from side to side, a. supportprojecting forwardly from said main frame and adapted to limit downward movement of said boom and form a support therefor during the gathering operation, a striker bar movable relative to said boom and disposed transversely across, the un-.- derside of said boom for engagement with said support when the boom is dropped, impact reducing means at each end of said bar including,

a supporting. member carried by said boom, hydraulic shock absorbing-means interposed between said supporting memberand said bar end, a bearing membercarried by said bar end, a second bearing memberdisposed adjacent said,sup-,- porting member, spring means interposed between said bearing members being effective to bias said bartoward-aposition spaced from said boom, and adjusting means carried by saidsupporting member for moving said second bearing member to vary the, bias in said spring to vary the impact reducing action thereof.

3. In a mucking machine, a track mounted main frame, a boom pivotally mounted on said mainframe, a scoop mounted on the freev end of said boom, means for elevating and swinging said boom from side to side, a support projecting forwardlyv from saidmain frame. and adaptedto limit downward movement of said boom and form a support therefor during thegathering operation, a striker bar carried bysaid boom and movable relative thereto and disposed transversely across the underside of said boom for engagement with said support when the boom is dropped, impact reducing meansincluding spring means and hydraulic shock absorbing means interposed between each end of said bar and a fixed member on said boom, said spring and hydraulic shock absorbing means being pivotally mounted relative to said striker bar to permit the latter to move, laterally relative to the boom, and means for limiting such relative lateral movement including inter-engageable vertically extending surfaces between the. boom and the striker bar whereby side thrustexertedon the striker bar will be carried directly by the boom.

4. In a mucking machine, a track mounted main frame, a boom pivotally mounted on said main frame, a scoop mounted on the free end of said boom, means for elevating and swinging said boom from side to side, a support projecting forwardly from said main frame and adapted to limit downward movement of said boom and form a support therefor during the gathering operation, a striker bar disposed transversely across the underside of said boom for engagement with said support when the boom is dropped, impact reducing means including, at each end of said bar, a lower supporting member pivotally mounted thereon, an upper supporting member fixed to said boom, hydraulic shock absorber means connecting said supporting members, a moveable adjustment member between said supporting members, spring means compressibly interposed between said lower supporting member and said adjustment member, adjustment screw means acting between said upper supporting member 6 and said movable adjustment member to vary the compression in said spring means, means acting between said bar and said boom to limit relative horizontal movement therebetween in directions parallel to and transverse to the longitudinal axis of said boom, and means carried by said boom for limiting downward movement of the bar relative to the boom when the latter is lifted from its support.

ANTHONY R. BIEDESS.

REFERENCES CITED The fo11owing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,213,684 Biedess Sept. 3, 1940 2,239,076 Biedess Apr. 22, 1941 2,282,378 Poole May 12, 1942 2,301,241 Biedess Nov. 10, 1942 

